The present invention relates generally to shift-lever devices for motor vehicles and more particularly to the shift-lever devices including a lock release mechanism.
Shift-lever devices have been proposed which include a lock mechanism operating based on a combination of shift-lock and key-lock mechanisms. The lock mechanism is constructed such that the key-lock mechanism prevents a shift lever from being moved from the parking position when parking a motor vehicle with an engine key removed, and the shift-lock mechanism prevents the engine key from being removed except when the shift lever is in the parking position, and the shift lever being moved therefrom unless a brake pedal is depressed when cruising the vehicle after engine start.
Specifically, when shifting the shift lever to the parking position P for engine stop, and removing the engine key for parking of the vehicle, a key cylinder is engaged with a steering shaft to obtain key lock, and an electric system of the vehicle is cut off. Referring to FIG. 6, an actuator 8 is turned off to press a plunger 7, which urges a lock lever 6 connected to the plunger 7 to rotate clockwise about a shaft 5 so as to move outside from a detent recess 3. However, since rotation of a key lever 10 connected to the key-lock mechanism through a joint rod 11 is restrained on the side of the key-lock mechanism, a pin 10a arranged in the rear of the key lever 10 touches the lock lever 6 to prevent rotation thereof. Thus, a position pin 2 is immovably restrained in the parking position P, disabling operation of the shift lever.
When removing key lock by inserting and rotating the engine key for cruising of the vehicle, the key cylinder is disengaged from the steering shaft which becomes rotatable by a steering wheel, and the key lever 10 becomes free of restraint to be rotatable. However, since the electric system is connected to turn on the actuator 8, and thus the lock lever 6 is kept being restrained in the detent recess 3, the position pin 2 is still immovably restrained in the parking position P.
When depressing the brake pedal for starting of the vehicle, the actuator 8 is turned off so that the lock lever 6 is moved outside of the detent recess 3 as indicated by two-dot chain line in FIG. 6, and the position pin 2 becomes free of restraint to be depressible through a knob of the shift lever, which allows the shift lever to be shifted to a desired range.
The shafts 5, 9 are supported by a gate wall formed with the detent recess 3, and the actuator 8 is fixed thereto. A support lever 13 operating with the key lever 10 to hold the position pin 2 is rotatably coaxially supported to the shaft 9. The support lever 13 serves to protect the key-lock mechanism by preventing direct transmission of a force produced when depressing the position pin 2 in the state as shown in FIG. 6. The key lever 10 and the support lever 13 are biased by a spring in the direction of holding the position pin 2.
With the known shift-lever devices, however, the shift-lock mechanism and the key-lock mechanism are mechanically connected to each other by a cable, etc., so that with the engine key removed, the shift lever cannot be shifted from the parking position P, resulting in difficulty of moving the vehicle.
It is, therefore, an object of the present invention to provide shift-lever devices including a mechanism for releasing a lock mechanism operating based on a combination of shift-lock and key-lock mechanisms.